Incandescent tube-igniter for gas-engines



[NVENTOR Patented Apr. ll, I899.

E. W. GRAEF.

INCANDESCENT TUBE IGNITER FOR GAS ENGINES.

(Application filed June 23, 1898.)

WWW/5% ATTORNEYS THE NORRlS PErERs co. nuoro-urrlo, WASHINGTON, n. c

NITED STATES PATENT OFFIC INCANDESCENT TUBE-IGNITER FOR GAS-ENGINES. I

SPECIFICATION forming part Of Letters Patent No. 622,892, dated April11, 1899. Application filed June 23,1898. Serial No. 684,234. (Nomodel.)

1 a resident of Baltimore, Maryland, have invented certain new anduseful Improvements in Incandescent Tube-Igniters for Gas-Engines, ofwhichthe followingis aspecification.

My invention relates to a gas-engine, and has for its object to apply anautomatic igniting device for igniting the gas in thecombustion-chamber.

It consists of a thimble inserted into the wall of thecombustion-chamber and projectin g through that wall into theexhaust-chamber, the interior of the thimble being in communication withthe combustion-chamber and the exterior of which is exposed to contactwith the exhaust-flame by which it is heated.

The drawing is a vertical section of the combustion-chamber, showing theinlet and exhaust valves and the automatic ignitingthimble inserted inthe wall of the combustion-chamber and projecting through the wall intothe exhaust-chamber.

Referring to the drawing, 1 is a valveohest; 2, a gas-supply pipe; 3, aninlet-valve; 4, a combustion-chamber within the valvechest 5, anexhaust-valve; 6, an exhaustchamber; '7, an exhaust-pipe.

8 is a thimble inserted in the wall of the combustion-chamber,projecting through that wall into the exhaust-chamber. The open end ofthe thimble is open to the combustionchamber and the closed end is inthe exhaustchamber.

9 is a mechanism for operating the exhaustvalve. (Not shown becauseunnecessaryto this case.) The combustion-chain her is connected in theusual manner with the cylinder of a gas-engine and theexhaust-valve-operating mechanism is connected in any usual manner withthe crank of the engine. The valvechest is supplied with any form ofelectric or gas igniting mechanism for its initial operation, thepurpose of the present device being to continue its operation after oncestarted. It is incapable of initiating the operation. Any electrical orgas apparatus for causing the first one or two explosions may beemployed, and therefore for the sake of simplicity they have beenomitted.

The operation of the device is as follows: As the engine is turned overgas will be drawn into the combustion-chamber and exploded by the actionof the electrical orother igniter. The motion of the piston will causethe exhaust-valve to open and the exploded burning gas will pass outthrough the exhaustchamber, surround the thimble 8, and heat it to thetemperature of the exhaust. This will be continued until the thimble 8,has been heated by the exhaust-flame to a temperature sufficient toexplode the incoming gas. The electrical or other igniter may then bethrown out of action and the explosion of the gas will continueautomatically under the influence of the heat imparted to the thimble 8by the exhaust-flame. The heat imparted to the thimble S by theexhaust-gas is sufficient to ignite the inflowing gas as soon as itenters the combustion-chamber;but I find that this does not occur, and Ihave concluded that the failure to so ignite the inflowing explosive gasis due to the fact that only the lower end of the thimble isheated to aminimum temperature, while the interior of the thimble after an exhaustis filled with gas which has already exploded from the last charge.Hence the fresh explosive gas which enters the combustion-chamber doesnot come in contact with the highly-heated part of the thimble until thereturn of the piston, when the gas contained in the combustion-chamberand the cylinder is compressed by the piston, and the gas in the thimbleis also compressed under the explosive gas which is above it until theexplosive gas is brought into contact with the highly-heated part of thethimble, when an explosion will occur. It is also probable that thecompression of the gas in the combustion-chamber also increases itstempepature and aids the combustion.

Havlng thus describedvmy invention, what I claim, and desire to secureby Letters Patent, is

An automatic igniter for gas-engines, which consists of a thimbleinserted in the wall of the combustion-chamber, the interior of which isin communication with said chamber and the exterior of which projectsinto the exhaustchamber, substantially as described.

Signed by me, at Baltimore, Maryland, this ith day of June, 1898.

ERNEST W. GRAEF.

Witnesses:

GEORGE KENT, Gno. O. MoRRIsoN.

